13C-UBT using an infrared spectrometer for detection of Helicobacter pylori and for monitoring the effects of lansoprazole.

The stable isotope [13C]-labeled urea breath test (13C-UBT) is very useful for detecting Helicobacter pylori. Conventionally, a mass spectrometer is used to measure the presence of 13CO2 in breath. However, this technique is complex and expensive. Therefore, we carried out the 13C-UBT using an easy-to-operate infrared spectrometer, and we studied its usefulness. The 95 subjects included 35 patients with gastric ulcers, 32 with duodenal ulcers, 13 with gastroduodenal ulcers, some patients with nonulcer gastroduodenal disease, and normal controls. The 13C-UBT was negative in normal controls and positive in 86 of 91 (95%) patients with illness. Peaks appeared 15 to 30 min after [13C]urea administration. The 33 patients who were 13C-UBT-positive were then given lansoprazole 30 mg/day and the 13C-UBT was repeated after 8 to 16 weeks. Lansoprazole was found to be effective in patients who exhibited peak 13CO2 values that were at least two-thirds less than the pretreatment values. This effect was seen in 16 patients (48%), 13 of whom (81%) had gastric ulcers. Thirteen of the 17 patients (76%) who exhibited no effect had duodenal ulcers, and there were clear treatment response differences between the two types of ulcers.